Experimental and theoretical mineral physics
The overwhelming majority of Earth's interior is not accessible to direct sampling or observation. Most of our understanding is based on remote sensing techniques (e.g., seismology). To interpret such observations, it is essential to have complimentary laboratory measurements. In his High-Pressure Mineral Physics Laboratory, Prof. Brown and his research group have an interdisciplinary program involving a variety of experimental and theoretical approaches. They seek an understanding of Earth based on an atomic-level understanding of constituent minerals. The underlying goal is an understanding of the thermal and compositional state of the Earth's interior and its contribution to observed dynamical behavior.
Current high pressure/high temperature work includes :
(1) measurement of elastic constants and thermal diffusivities of mineral under mantle conditions,
(2) studies of equations of state and viscosities of fluids, and
(3) measurements of elastic constants of metals under conditions approaching Earth's core. These data provide a comprehensive framework for the understanding of how Earth and other planets work.
Fellow of the American Geophysical Union, 2000
Néel Medalist, European Geophysical Society, 2002: in recognition of outstanding achievements in the fertilization of the Earth Sciences by the transfer and application of fundamental theory and/or experimental techniques of solid-state physics.
Brown, J.M., J.N. Fritz, and R.S. Hixson, Hugoniot data for iron, J. Appl. Phys, 88 (9), 5496-8, 2000.
Zaug, J.M., E.H. Abramson, J.M. Brown, L.J. Slutsky, C.M. Aracne-Ruddle, and D.W. Hansen, A Study of the Elasticity of Ta at High Temperature and Pressure, in "Science and Technology of High Pressure," edited by M.H. Manghnani, W.J. Nellis, and M.F. Nicol, pp. 804-6, Universities Press, Hyderabad, India, 2000.
Abramson, E.H., J.M. Brown, and L.J. Slutsky, Speed of Sound and Thermal Diffusivity in Fluid Oxygen to 12 GPa, in "Science and Technology of High Pressure," edited by M.H. Manghnani, W.J. Nellis, and M.F. Nicol,
pp. 807-9, Universities Press, Hyderabad, India, 2000.
Boness, D.A., J. M. Brown, M. Morgan, J. Madamba, Disagreement between shock and static temperature data: Calculation of argon optical transmittance in laser-heated diamond anvil cells, in Shock Compression of Condensed matter -1999, edited by , p 173-6, AIP Conference Proceedings, 505, 2000.
Crowhurst, J.C., E.H. Abramson, L.J. Slutsky, J.M. Brown, J.M. Zaug, and M.D. Harrell, Surface acoustic waves in the diamond anvil cell: An application of impulsive stimulated light scattering, Phys. Rev. B, 64, 100103-6, 2001.
Abramson, E.H., J.M. Brown, L.J. Slutsky, S. Wiryana, Measuring speed of sound and thermal diffusivity in the diamond-anvil cell, International J. Thermophys. 22, 405-414, 2001.
Brown, J. M., The equation of state for iron to 450 GPa: Another high pressure phase?, Geophys. Res. Lett , 28, 4339-42, 2001
Abramson, E.H., .M. Brown, and L.J. Slutsky, Thermal diffusivity of water, J. Chem. Phys., 115, 10461-3, 2001.
Brown, J. M., And J. N. Fritz, Thermodynamics properties of iron: New initially porous Hugoniot data, to be
Harrell, M. D., J. M. Brown, Thermal conductivity of mantle silicates to 1300K, in preparation